1. Field of the Invention
The invention relates generally to a device for gripping and displacing material, such as roughage for animals, in particular to such a device provided with a gripper for use in combination with a feeding column for distributing feed to a number of animals.
2. Description of the Related Art
Devices are known for gripping and displacing material. Such devices may comprise a pair of articulated grabs suspended from a gantry or the like. Different forms of grab e.g. buckets, forks, clamps etc may be used according to the type of material to be displaced. Gripping devices are also known in which a first fork-gripper is surrounded by a double bucket-gripper. By means of the fork-gripper large pieces of material are gripped, whereas by means of the bucket-gripper it is possible also to grip smaller parts of material. Material parts falling from the fork-gripper may be collected by the bucket-gripper. However, if the bucket-gripper is not completely closed, for example owing to material parts being clamped between the two bucket halves, the risk of material parts falling unintentionally from the gripping device during transport or during lifting of the gripper always remains. A device of this type is known from Japanese Patent Publication JP 2002/187688 in which a fork-gripper and bucket-gripper move as a single piece between spread and grasp positions.
Unintentional spillage from a grab is particularly inconvenient where the grab must pass over areas where it is not desired that material should fall. This is particularly the case in automated environments where operators may not be available to tidy up. Material falling over or into machinery may also form a hazard for continued operation of the machinery. Thus, there is a particular need for a gripping device providing improved cleanliness in the transport area.